1. Field of the Invention
The present invention relates to an endoscope apparatus suitable to bend a bending portion provided for a tip of an inserted portion of an endoscope by using a joystick.
2. Prior Art Statement
Conventionally, an endoscope apparatus has been widely used. The endoscope apparatus observes an examined site and performs various processings by inserting a long inserted portion into a body cavity. Also, in an industrial field, an (industrial) endoscope apparatus has been widely used. The (industrial) endoscope apparatus can observe and inspect an internal defect, corrosion, etc. of a boiler, turbine, engine, chemical plant, and the like.
The above-mentioned endoscope apparatus is structured such that a bending portion capable of being manually operated is provided at a base-end side of a tip of the long inserted portion. The inserted portion has a CCD, etc. which is an image pickup means at the tip and a camera control unit (hereinafter, referred to as a CCU) at the side near hand.
Image information obtained by using the CCD is transmitted to the CCU so that a video signal is generated. An endoscope image can be displayed by supplying the video signal to a display apparatus such as an LCD, a CRT, or the like.
Bending operation of the bending portion can be remotely operated by an operational remote controller for endoscope (hereinafter, referred to as an operational remote controller). That is, the endoscope apparatus has therein a motor for bending which can be controlled by the operational remote controller. In the endoscope apparatus, a wire placed at the bending portion is towed and loosened by using a power of the motor, thereby enabling the bending portion to be remotely bent.
As the endoscope apparatus having the operational remote controller, an endoscope apparatus in which a joystick is provided as the operational remote controller for bending operation is proposed as disclosed in Japanese Laid-open Patent Publication No. 10-328131. Incidentally, a detailed operating method of the joystick in the endoscope apparatus is not disclosed in Japanese Laid-open Patent Publication No. 10-328131.
Also, for example, in an endoscope of European Patent Application Publication No. 0543738A1, an endoscope apparatus in which an electrically-driven bent inserted portion detachable from a processor control module is operated by a joystick is proposed. This reference discloses that, in the above-mentioned endoscope apparatus, the electrically-driven bent inserted portion is positionally controlled by the joystick. Further, the reference discloses that, in the above-mentioned endoscope apparatus, a bent shape is electrically perked (locked against bending). Incidentally, European Patent Application Publication No. 0543738A1 does not disclose a detailed operating method of an operational button, etc. for positional control and locking against bending in the endoscope apparatus.
The joysticks have variable resistors in which resistances are varied depending on inclination angles of a lever. The joysticks can output an analog voltage value in accordance with the inclination angles of the lever. As disclosed in European Patent Application Publication No. 0543738A1, the joystick is frequently used for the positional control.
As the positional control using the above-described joystick, a method for proportioning the inclination angle of the lever to an offset of a controlled target can be considered. For example, the positional control using the joystick has an advantage that an operator can easily grasp an actual angle of bending by proportioning the inclination angle of the lever (bending lever) to an inclination angle of the tip of the inserted portion.
However, when bending with an only fine angle, in the positional control using the joystick, the operational angle of the bending lever also must become fine. Thus, the operator needs to concentrate his attention to his fingertip and, therefore, fatigue from the operation is increased.
Then, in the endoscope-apparatus, a method (bending control at a constant speed) in which an output of the joystick is handled as a signal indicating only a direction, not as an analog value corresponding to the inclination angle of the level, and the bending portion is bent in a pushed-down direction of the lever at a constant speed; is put into practical use in order to solve the disadvantage of the positional control. Further, the endoscope apparatus, is sometimes employed, having a function switching the positional control and the bending control at the constant speed.
In the case of the bending control at the constant speed, the operator cannot arbitrarily change a bending speed. Therefore, in the endoscope apparatus using the bending control at the constant speed, the constant speed is set to a slow speed, that is, driving in a slow mode is frequent. When using the slow mode as the bending control at the constant speed, the operability at the time of fine adjustment of the bending angle is excellent, however, the above endoscope apparatus has a problem that it takes a long time until the inclination angle reaches a desired bending angle. In contrast, when using a fast speed as the bending control at the constant speed, the above endoscope apparatus has a problem that the operability at the time of fine adjustment is remarkably reduced.
In the endoscope apparatus disclosed in European Patent Application Publication No. 0543738A1, the bending locking of the bending portion is on by operating a bending lock switch which is laid out at a position different from that of the joystick for bending operation. Therefore, in the endoscope apparatus, the bending locking cannot be performed by one-hand operation.
In the endoscope apparatuses, generally, it is impossible to confirm whether or not the bending portion is locked and, therefore, it is confirmed by employing light on/off of an LED, etc. near a switch. However, the operator must look aside from a monitor on which an endoscope image, etc. is displayed to confirm whether or not the bending portion is locked by employing light on/off of the LED, etc., thereby the operability is inferior.
When the lever is not operated, the joystick is automatically returned near a neutral position by energizing power of a spring. However, there is a problem that the neutral position of the automatic returned lever is largely varied depending on precision of a spring or mechanism of the joystick.
In the inventor""s opinion, the periphery of the neutral position is set to an insensitive band taking account of the variation. When the lever is located at the neutral position, a method for stopping an output of a positional information signal can be considered.
However, the above-mentioned method has a problem that the lever operation is not available within a predetermined range near the neutral position and the bending operation is possible only by relatively largely inclining the lever.
On the other hand, in a conventional endoscope apparatus for always transmitting positional information without setting the insensitive band, even if the lever is not operated, the positional information of the lever is outputted from the joystick. Therefore, the conventional endoscope apparatus has a problem that processing efficiency of a CPU is reduced when using a controller for controlling by using the positional information of the lever from the joystick.
For the above reasons, in the endoscope apparatuses, the precision of operability of the joystick cannot be increased.
Operational remote controllers with the above-mentioned joysticks having a display for supplying a video signal which is signal-processed by the CCU to display the signal as an observed image are proposed as disclosed in, for example, Japanese Laid-open Patent Publication No. 10-328131 and U.S. Pat. No. 5,373,317.
The operational remote controller disclosed in Japanese Laid-open Patent Publication No. 10-328131 is structured such that a display and a joystick is provided for a case having a predetermined volume. Since the above operational remote controller has only the joystick for bending operation, it has a problem that operations other than the bending control cannot be executed.
In contrast, the operational remote controller disclosed in U.S. Pat. No. 5,373,317 is provided-with a display, a joystick, and key switches for various operations. The motor, and a signal processing control unit for processing an image pickup signal from image pickup means are provided in a case.
Since the above operational remote controller has the motor, signal processing control unit, and display, there is a problem that the outer shape of the case is large, the weight is heavy, and various operations are impossible while supporting the above operational remote controller by one-handed grasping. Further, since the key switches are adjacent to the display in the above operational remote controller, there is also a problem that it is not user-friendly because the key switches are operated only by positioning the hand aside from the joystick or only by operation using the hand which grasps an inserted portion.
It is one object of the present invention to provide an endoscope apparatus capable of improving bending operability using a joystick.
It is another object of the present invention to provide an endoscope apparatus capable of improving the operational precision of bending using the joystick.
It is further another object of the present invention to provide an endoscope apparatus capable of user-friendlily performing operation necessary for observation and inspection by one hand while performing bending operation with small size and light weight.
According to the present invention, an endoscope apparatus includes: bending drive means for bending a bending portion provided to a tip of an inserted portion; an operating unit for bending and operating the bending portion by inclining a lever; and control means for allowing the bending drive means to bend and operate the bending portion based on information from the operating unit, for detecting the neutral position for every automatically returning of the lever to the neutral position, and for setting a predetermined range from the detected neutral position to an insensitive band to prohibit bending driving of the bending portion by the bending drive means.
According to the present invention, an endoscope apparatus includes: bending drive means for bending a bending portion provided for a tip of an inserted portion; a bending operating unit for bending the bending portion by inclining a lever; and a plurality of operating units, which are provided for remotely controlling the endoscope apparatus, other than said bending operating unit and are provided distributively on the front surface and a back surface of a case of an operational remote controller for endoscope.
The above and many other objects, features, and advantages of this invention will become apparent from the ensuing detailed description of one preferred embodiment, which should be read in conjunction with the accompanying drawing.